A small dormant geyser in the Upper Geyser Basin of Yellowstone National Park, Wyoming. Yellowstone’s underground “plumbing” is constantly changing, mainly due to earthquakes from volcanic activity. In the early 20th century this was an active and quite popular geyser. Its frequent eruptions would spray up to seven meters high, after which all the water would “economically” drain away until the next eruption. The eruptions petered out in the 1920s.
When I took this picture in 1991, Economic Geyser was a pool filled and surrounded with colorful microbes. Boardwalk construction in 1999 changed the geyser’s “plumbing” again, bringing in hotter water and even a few eruptions that killed off the resident organisms.